Energy and Human Ambitions on a Finite Planet, 2021a

12 Wind <strong>Energy</strong> 191
demonstrates the aspects covered in the previous paragraph: “cutting
in” just above 3 m/s <strong>and</strong> maxing out (saturating) beyond about 12 m/s.
In between, it closely follows a cubic function at an overall efficiency of
44% (blue curve).
12.3 Wind Installations
Global wind installations are rising rapidly, currently (as of 2020) above
600 GW of installed capacity. 23 23: A small fraction of this is realized, due
Table 12.2 lists the major players, in to the capacity factor.
terms of installed capacity, average generation, fraction of total energy, 24
24: To compare wind to total energy, we
capacity factor, <strong>and</strong> share of global wind generation. The amount of follow the thermal equivalent convention
wind energy in each country depends on a combination of how much discussed for Table 10.3 (p. 170)
wind is available in the country, how fast electricity dem<strong>and</strong> is growing,
electrical infrastructure, <strong>and</strong> political interest in renewable energies.
Table 12.2: Global wind installations in 2018 [78–84]. The top six countries capture 85% of the global total.
Country GW installed GW average cap. fac. (%) energy fraction (%) global share (%)
China 184 41.8 22.7 3.0 33
U.S. 97 31.4 32.4 2.7 25
Germany 59 12.7 21.4 8.3 10
India 35 6.5 18.5 2.3 5.2
Spain 23 5.4 23.5 8.3 4.3
UK 21.7 6.5 30.0 6.9 5.2
World Total 592 ∼ 125 21.1 2.0 100
0 2 4 6 8
Wind generation (GW)
Figure 12.8: Wind power by state, in terms
of average generation, in GW, in 2018. The
color scale may seem unhelpful, but the
unavoidable truth is that many states don’t
have a lot going on, <strong>and</strong> Texas is so dominant
as to render other states almost insignificant.
A logarithmic color scale could
help, but then the important lesson on the
gross disparity might go unappreciated.
In 2018, the U.S. had about 94 GW of installed wind capability. 25 This 25: From tables 1.14.B <strong>and</strong> 6.2.B in [85]
number has recently surpassed hydroelectric installed capacity (about
80 GW). Both are impacted by capacity factors, which for wind averages
33% in the U.S., while hydropower is just over 40%. The net effect is that
the generation for the two is pretty comparable. 26 Where is the wind 26: ...aswealso saw in Table 10.3 (p. 170)
power in the U.S. installed? Figure 12.8 shows that Texas wins, at 8.7 GW.
Oklahoma is a distant second at 3.2 GW, Iowa at 2.5 GW. California is in
fifth place at 1.6 GW.
© 2021 T. W. Murphy, Jr.; Creative Commons Attribution-NonCommercial 4.0 International Lic.;
Freely available at: https://escholarship.org/uc/energy_ambitions.